getHistogram() -> getSnapshot()

Author: nicktindall

server/src/main/java/org/elasticsearch/common/metrics/ExponentialBucketHistogram.java

@@ -63,7 +63,7 @@ public void addObservation(long observedValue) {
      * @return An array of frequencies of handling times in buckets with upper bounds as returned by {@link #getBucketUpperBounds()}, plus
      *         an extra bucket for handling times longer than the longest upper bound.
      */
-    public long[] getHistogram() {
+    public long[] getSnapshot() {
         final long[] histogram = new long[BUCKET_COUNT];
         for (int i = 0; i < BUCKET_COUNT; i++) {
             histogram[i] = buckets[i].longValue();
@@ -79,7 +79,7 @@ public long[] getHistogram() {
      */
     public long getPercentile(float percentile) {
         assert percentile >= 0 && percentile <= 1;
-        final long[] snapshot = getHistogram();
+        final long[] snapshot = getSnapshot();
         final long totalCount = Arrays.stream(snapshot).sum();
         long percentileIndex = (long) Math.ceil(totalCount * percentile);
         // Find which bucket has the Nth percentile value and return the upper bound value.

server/src/main/java/org/elasticsearch/http/HttpRouteStatsTracker.java

@@ -102,7 +102,7 @@ public HttpRouteStats getStats() {
             responseStats.count().longValue(),
             responseStats.totalSize().longValue(),
             responseStats.getHistogram(),
-            responseTimeMillisHistogram.getHistogram()
+            responseTimeMillisHistogram.getSnapshot()
         );
     }
 }

server/src/main/java/org/elasticsearch/transport/TcpTransport.java

@@ -1001,8 +1001,8 @@ public final TransportStats getStats() {
             bytesRead,
             messagesSent,
             bytesWritten,
-            networkService.getHandlingTimeMillisHistogram().getHistogram(),
-            outboundHandlingTimeMillisHistogram.getHistogram(),
+            networkService.getHandlingTimeMillisHistogram().getSnapshot(),
+            outboundHandlingTimeMillisHistogram.getSnapshot(),
             requestHandlers.getStats()
         );
     }

server/src/test/java/org/elasticsearch/common/metrics/ExponentialBucketHistogramTests.java

@@ -18,46 +18,46 @@
 
 public class ExponentialBucketHistogramTests extends ESTestCase {
 
-    public void testHistogram() {
+    public void testSnapshot() {
         final ExponentialBucketHistogram histogram = new ExponentialBucketHistogram();
 
-        assertArrayEquals(new long[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(0L);
-        assertArrayEquals(new long[] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(1L);
-        assertArrayEquals(new long[] { 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(2L);
-        assertArrayEquals(new long[] { 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(3L);
-        assertArrayEquals(new long[] { 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(4L);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(127L);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(128L);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(65535L);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0 }, histogram.getSnapshot());
 
         histogram.addObservation(65536L);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1 }, histogram.getSnapshot());
 
         histogram.addObservation(Long.MAX_VALUE);
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 2 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 2 }, histogram.getSnapshot());
 
         histogram.addObservation(randomLongBetween(65536L, Long.MAX_VALUE));
-        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 3 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 1, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 3 }, histogram.getSnapshot());
 
         histogram.addObservation(randomLongBetween(Long.MIN_VALUE, 0L));
-        assertArrayEquals(new long[] { 2, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 3 }, histogram.getHistogram());
+        assertArrayEquals(new long[] { 2, 1, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 3 }, histogram.getSnapshot());
     }
 
     public void testHistogramRandom() {
@@ -73,7 +73,7 @@ public void testHistogramRandom() {
             histogram.addObservation(between(lowerBound, upperBound));
         }
 
-        assertArrayEquals(expectedCounts, histogram.getHistogram());
+        assertArrayEquals(expectedCounts, histogram.getSnapshot());
     }
 
     public void testBoundsConsistency() {